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    <title>ShellCheck: SC2160 – Instead of `[ true ]`, just use `true`.</title>
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    <h1>SC2160 – ShellCheck Wiki</h1>
    <a href="https://github.com/koalaman/shellcheck/wiki/SC2160">See this page on GitHub</a>
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    <h2 id="instead-of--true--just-use-true">Instead of
<code>[ true ]</code>, just use <code>true</code>.</h2>
<h3 id="problematic-code">Problematic code:</h3>
<div class="sourceCode" id="cb1"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb1-1"><a href="SC2160.html#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="cf">if</span> <span class="bu">[</span> true <span class="bu">]</span></span>
<span id="cb1-2"><a href="SC2160.html#cb1-2" aria-hidden="true" tabindex="-1"></a><span class="cf">then</span></span>
<span id="cb1-3"><a href="SC2160.html#cb1-3" aria-hidden="true" tabindex="-1"></a>  <span class="bu">echo</span> <span class="st">&quot;always triggers&quot;</span></span>
<span id="cb1-4"><a href="SC2160.html#cb1-4" aria-hidden="true" tabindex="-1"></a><span class="cf">fi</span></span></code></pre></div>
<h3 id="correct-code">Correct code:</h3>
<div class="sourceCode" id="cb2"><pre class="sourceCode sh"><code class="sourceCode bash"><span id="cb2-1"><a href="SC2160.html#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="cf">if</span> <span class="fu">true</span></span>
<span id="cb2-2"><a href="SC2160.html#cb2-2" aria-hidden="true" tabindex="-1"></a><span class="cf">then</span></span>
<span id="cb2-3"><a href="SC2160.html#cb2-3" aria-hidden="true" tabindex="-1"></a>  <span class="bu">echo</span> <span class="st">&quot;always triggers&quot;</span></span>
<span id="cb2-4"><a href="SC2160.html#cb2-4" aria-hidden="true" tabindex="-1"></a><span class="cf">fi</span></span></code></pre></div>
<h3 id="rationale">Rationale:</h3>
<p>This is a stylistic suggestion to use <code>true</code> instead of
<code>[ true ]</code>.</p>
<p><code>[ true ]</code> seems to suggest that the value "true" is
somehow relevant to the statement. This is not the case, it doesn't
matter. You can replace it with <code>[ false ]</code> or
<code>[ wombat ]</code>, and it will still always be true:</p>
<table>
<thead>
<tr class="header">
<th>String</th>
<th>In brackets</th>
<th>Outside brackets</th>
</tr>
</thead>
<tbody>
<tr class="odd">
<td>true</td>
<td>true</td>
<td>true</td>
</tr>
<tr class="even">
<td>false</td>
<td>true</td>
<td>false</td>
</tr>
<tr class="odd">
<td>wombat</td>
<td>true</td>
<td>unknown command</td>
</tr>
</tbody>
</table>
<p>It's therefore better to use it without brackets, so that the "true"
actually matters.</p>
<h3 id="exceptions">Exceptions:</h3>
<p>None.</p>
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